Breeding for aluminum tolerance

Abstract

Aluminum (Al) toxicity is one of the greatest limitations to agriculture in acid soils, principally in the tropical regions. In these areas, crop management practices, including massive application of limestone, were adopted for the implementation of commercial agriculture. However, even in well-managed soils, subsurface layers might have a high acidity and high Al saturation, limiting root development in sensitive cultivars. Thus, breeding for Al tolerance is a key point to achieve high yield and to enhance the stability of cultivars. Nowadays, great effort has been applied to the identification of genes associated to the Al tolerance aiming the incorporation of favorable alleles in elite cultivars through the integration of conventional breeding and molecular tools. In this chapter, we are discussing some topics related to the effects of Al in plants, mechanisms and inheritance of Al tolerance, passing to practical points like evaluation of this trait in annual crops, strategies and breeding methods, and, finally, biotechnology applied to the breeding for tolerance to Al toxicity.